Does redis allocate memory like memcached for keys, in which as long as a key fits in a 'memory slab' of length X, there is no incremental memory required between say the 'foo' key and the 'foo2' key? Or, is the amount of memory required monotonically increasing each time an additional character is added to the key?

What about for the value? Is it also monotonically increasing or subject to the 'slab allocator' concept in redis?